The use of zeolite promoted cracking catalysts is well known. U.S. Pat. No. 3,140,249 to Plank et al is typical of the early patents in this area. These patents generally disclose the use of a faujasitic type zeolite having a silica to alumina ratio of about 3 to 6 that has exchanged therein a fairly substantial quantity of rare earth oxides, distended in a matrix such as silica, silica-alumina, silica-zirconia, alumina, et. The preferred catalysts comprise the rare earth exchange faujasitic zeolites in a silica-alumina matrix.
Continuing efforts have been made to improve these catalysts by making them more stable, more resistant to high temperature and more economical. One of the recurring problems is the use of the relatively rare and quite costly rare earth salts in the preparation of these catalysts. The process of the instant application prepares a stable active zeolite containing catalyst that minimizes the amount of rare earth contained therein.